Divers/Loons
Great Northern Diver or Common Loon (Gavia immer).
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Aves Order: Gaviiformes Wetmore & Miller, 1926 Family: Gaviidae J.A. Allen, 1897 Genus: Gavia Forster, 1788
Global distribution of Gaviidae (breeding and winter ranges combined)
Species
Gavia stellata Gavia arctica Gavia pacifica Gavia immer Gavia adamsii

The Loons (N.Am.) or Divers (UK/Ireland) are a group of aquatic birds found in many parts of North America and northern Europe. A loon is the size of a large duck or small goose, which it somewhat resembles in shape when swimming, but they are completely unrelated to waterfowl. Their plumage is largely black-and-white, with grey on the head and neck in some species, and a white belly, and they have a spear-shaped bill. All living species of loons are members of one genus (Gavia) in a family (Gaviidae), and order (Gaviiformes) all of their own. Image File history File links Download high-resolution version (925x625, 301 KB) Summary Licensing File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Loon ... Binomial name Gavia immer (Brunnich, 1764) The Great Northern Diver, known in North America as the Common Loon (Gavia immer), is a large member of the loon, or diver, family. ... Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ... Animalia redirects here. ... Typical Classes Subphylum Urochordata - Tunicates Ascidiacea Thaliacea Larvacea Subphylum Cephalochordata - Lancelets Subphylum Myxini - Hagfishes Subphylum Vertebrata - Vertebrates Petromyzontida - Lampreys Placodermi (extinct) Chondrichthyes - Cartilaginous fishes Acanthodii (extinct) Actinopterygii - Ray-finned fishes Actinistia - Coelacanths Dipnoi - Lungfishes Amphibia - Amphibians Reptilia - Reptiles Aves - Birds Mammalia - Mammals Chordates (phylum Chordata) include the vertebrates, together with... For other meanings of bird, see bird (disambiguation). ... Frank Alexander Wetmore (June 18, 1886 _ December 7, 1978) was an American ornithologist and avian paleontologist. ... Joel Asaph Allen (July 19, 1838 - August 29, 1921) was an American zoologist and ornithologist. ... Johann Reinhold Forster Johann Reinhold Forster (October 22, 1729 - December 9, 1798) was a German naturalist of Scottish descent. ... Image File history File links No higher resolution available. ... Binomial name Gavia stellata (Pontopiddan, 1763) Gavia, meaning sea smew (although Divers are not Smew), stella meaning starred, in reference to the white speckling on its back in winter. ... Binomial name Gavia arctica (Linnaeus, 1758) Black-throated Diver, known in North America as Arctic Loon (Gavia arctica), is a medium-sized member of the loon or diver family. ... Binomial name Gavia pacifica (Lawrence, 1858) The Pacific Diver (Gavia pacifica), known in North America as the Pacific Loon, is a medium-sized member of the loon, or diver, family. ... Binomial name Gavia immer (Brunnich, 1764) The Great Northern Diver, known in North America as the Common Loon (Gavia immer), is a large member of the loon, or diver, family. ... Binomial name Gavia adamsii (Gray,GR, 1859) The White-billed Diver, known in North America as Yellow-billed Loon (Gavia adamsii), is the largest member of the loon or diver family, at 77-90cm in length with a 135-150 cm wingspan, although it is only marginally larger than the... World map showing North America A satellite composite image of North America. ... This article is 150 kilobytes or more in size. ... // Subfamilies Dendrocygninae Oxyurinae Anatinae Merginae Duck is the common name for a number of species in the Anatidae family of birds. ... Falcated Duck at Slimbridge Wildfowl and Wetlands centre, Gloucestershire, England Wildfowl or waterfowl, also waterbirds, is the collective term for the approximately 147 species of swans, geese and ducks, classified in the order Anseriformes, family Anatidae. ... Two feathers Feathers are one of the epidermal growths that form the distinctive outer covering, or plumage, on birds. ... For other uses of the word, please see Genus (disambiguation). ... In biological classification, family (Latin: familia, plural familiae) is 1) a rank or 2) a taxon in that rank. ... Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ...

Ecology

Loons are excellent swimmers, using their feet to propel themselves above and under water and the wings for assistance. Because their feet are far back on the body, loons are badly adapted to moving on land. They usually avoid coming ashore, except for nesting.

All loons are decent fliers though the larger species have some difficulty taking off, needing a run into the wind to pick up enough velocity to get airborne. Only the Red-throated Diver can take off from land. Once airborne, their considerable stamina allows them to migrate long distances southwards in winter, where they reside in coastal waters. Loons can live as long as 30 years. Binomial name Gavia stellata (Pontopiddan, 1763) Gavia, meaning sea smew (although Divers are not Smew), stella meaning starred, in reference to the white speckling on its back in winter. ...

Diet

Loons eat fish, amphibians, and crustaceans, which they hunt for under water, finding their prey by sight. This includes crayfish, frogs, snails, salamanders and leeches. They prefer clear lakes because it is easier to see prey. The loon's pointy bill is used to stab or grasp prey. Vertebrate prey is eaten head first to facilitate swallowing. Subclasses and Orders Order Temnospondyli - extinct Subclass Lepospondyli - extinct Subclass Lissamphibia   Anura   Caudata   Gymnophiona Amphibians (class Amphibia; from Greek αμφις both and βιος life) are a taxon of animals that include all living tetrapods (four-legged vertebrates) that do not have amniotic eggs, are ectotherms, and generally spend part of their time...

To help digestion, loons swallow small pebbles from the bottom of a lake^{[citation needed]}. Similar to grit eaten by chicken, these gastroliths may assist the loon's gizzard in crushing the hard parts of the loon's food (the exoskeletons of crustaceans and the bones of frogs and salamanders), as prey is swallowed whole. This article or section does not cite its references or sources. ... Gastroliths (stomach stones or gizzard stones) are rocks, which are or have been held inside the digestive tract of an animal. ... The gizzard is an adapted stomach that is found in birds, earthworms, and other animals. ... An exoskeleton, in contrast to an endoskeleton, is an external anatomical feature that supports and protects an animals body. ...

Reproduction

During the summer, loons nest on fresh water lakes and/or large ponds. Smaller bodies of water (up to 0.5 km²) will usually only have one pair. Larger lakes will have more than one pair, with each pair occupying a bay or section of the lake. Square kilometre (US spelling: Square kilometer), symbol km², is an SI unit of surface area. ...

Loons build their nests close to the water, preferring sites that are completely surrounded by water. They may use the same site from year to year. Loons will use a variety of materials found nearby to build their nests — pine tree needles, leaves, grass, moss, and sometimes clumps of mud. Both the male and female help with nest building and with incubation, which usually lasts 26-31 days. If the eggs are lost, the pair may re-nest, often in the same general location.

Usually one or two eggs are laid in June. Loon chicks are precocial, able to swim right away, but are often seen riding on their parents' back. This behavior allows the chicks to rest, conserve heat, and avoid predators such as large carnivorous fish, snapping turtles, gulls, eagles and crows. After a day or two, chicks do not return to the nest anymore. In biology, precocial species are those that are relatively mature and mobile from the moment of birth or hatching. ...

Chicks are fed exclusively by their parents for the first few weeks of life, and up until eight weeks of age, stay with their parents most of the time. After eight weeks, chicks will begin to dive for some of their own food. By 11 or 12 weeks of age, chicks are able to gather almost all of their own food and may be able to fly.

A pair may mate for life, although recent banding studies have shown that loons will sometimes switch mates after a failed nesting attempt and even between nesting attempts in the same season^{[citation needed]}.

Migration

Common Loons generally migrate to oceans for the winter because their poor walking ability and need for a "runway" of open water to fly leave them in danger if their lakes freeze. In February 2007, scientists found 17 dead loons at Lake Winnipesaukee in New Hampshire and speculated that the uncommonly warm early winter had confused the loons, leaving them vulnerable when the lake finally froze weeks later than normal. [1] Lake Winnipesaukee at Sunset Lake Winnipesaukee is the largest lake in New Hampshire. ... This article does not cite its references or sources. ...

Systematics and evolution

Arctic Loon/Black-throated Diver

Image File history File links Size of this preview: 800 × 542 pixel Image in higher resolution (1050 × 711 pixel, file size: 594 KB, MIME type: image/jpeg) Description: Arctic Loon (Gavia arctica) on Nest Creator: Robert Bergman URL: Fish and Wildlife Service File links The following pages on the English... Image File history File links Size of this preview: 800 × 542 pixel Image in higher resolution (1050 × 711 pixel, file size: 594 KB, MIME type: image/jpeg) Description: Arctic Loon (Gavia arctica) on Nest Creator: Robert Bergman URL: Fish and Wildlife Service File links The following pages on the English...

Species

All living divers are classed in the genus Gavia.

• Red-throated Diver or Red-throated Loon, Gavia stellata.
• Black-throated Diver or Arctic Loon, Gavia arctica.
• Pacific Diver or Pacific Loon, Gavia pacifica - sometimes included in G. arctica
• Great Northern Diver or Common Loon, Gavia immer.
• White-billed Diver or Yellow-billed Loon, Gavia adamsii

Binomial name Gavia stellata (Pontopiddan, 1763) Gavia, meaning sea smew (although Divers are not Smew), stella meaning starred, in reference to the white speckling on its back in winter. ... Binomial name Gavia arctica (Linnaeus, 1758) Black-throated Diver, known in North America as Arctic Loon (Gavia arctica), is a medium-sized member of the loon or diver family. ... Binomial name Gavia pacifica (Lawrence, 1858) The Pacific Diver (Gavia pacifica), known in North America as the Pacific Loon, is a medium-sized member of the loon, or diver, family. ... Binomial name Gavia immer (Brunnich, 1764) The Great Northern Diver, known in North America as the Common Loon (Gavia immer), is a large member of the loon, or diver, family. ... Binomial name Gavia adamsii (Gray,GR, 1859) The White-billed Diver, known in North America as Yellow-billed Loon (Gavia adamsii), is the largest member of the loon or diver family, at 77-90cm in length with a 135-150 cm wingspan, although it is only marginally larger than the...

Relationships and evolution

The loons were formerly often considered to be the most ancient of the northern hemisphere bird families; this idea grew basically out of the perceived similarity of shape and (probably) habits between loons and the entirely unrelated extinct Cretaceous order Hesperornithiformes. However, the two groups are merely the product of convergent evolution and adapted in a similar way to a similar ecological niche. The Cretaceous Period is one of the major divisions of the geologic timescale, reaching from the end of the Jurassic Period (i. ... Families Hesperornithidae Hesperornithiformes are an extinct and highly specialized order of Cretaceous toothed birds. ... In evolutionary biology, convergent evolution is the process whereby organisms not closely related, independently evolve similar traits as a result of having to adapt to similar environments or ecological niches. ... Two lichenes species on a rock, in two different ecological niches In ecology, a niche is a term describing the relational position of a species or population in an ecosystem. ...

More recently, it has recently become clear that the Anseriformes (waterfowl) and the Galliformes are the most ancient groups of modern birds, while loons belong to a more modern radiation. What is also generally accepted as a fact is that loons and grebes are not closely related at all, but rather one of the most stunning examples of convergence in the known birds. The Sibley-Ahlquist taxonomy still allied the loons with the grebes in its paraphyletic "Ciconiiformes", and it is almost certain that the relationships of loons lie with some of the orders united therein. Alternatively, loons have tentatively been considered to share a rather close relationship with waders, penguins or procellariiform seabirds (Olson, 1985; Mayr, 2004). Families Anhimidae Anseranatidae Anatidae †Cnemiornithidae †Dromornithidae †Presbyornithidae The order Anseriformes contains about 150 species of birds in three families: the Anhimidae (the screamers), Anseranatidae (the Magpie-goose), and the Anatidae, which includes over 140 species of waterfowl, among them the ducks, geese, and swans. ... Families Megapodidae Numididae Odontophoridae Phasianidae Meleagrididae Tetraonidae Cracidae Mesitornithidae The Galliformes is an order of birds containing the turkeys, grouse, quails and pheasants. ... Genera Podiceps Tachybaptus Podilymbus Aechmophorus Poliocephalus Rollandia Grebes are members of the Podicipediformes order, a widely distributed order of freshwater diving birds, some of which visit the sea when migrating and in winter. ... The Sibley-Ahlquist taxonomy is a radical bird taxonomy based on DNA-DNA hybridization studies conducted in the late 1970s and throughout the 1980s. ... Paraphyletic - Wikipedia /**/ @import /skins-1. ... Families Scolopacidae Rostratulidae Jacanidae Thinocoridae Pedionomidae Burhinidae Chionididae Pluvianellidae Ibidorhynchidae Recurvirostridae Haematopodidae Charadriidae Dunlin (Calidris alpina). ... Modern genera Aptenodytes Eudyptes Eudyptula Megadyptes Pygoscelis Spheniscus For prehistoric genera, see Systematics Some penguins are curious. ... Families Procellariidae Diomedeidae Hydrobatidae Pelecanoididae Procellariiformes (from the Latin procella, a storm) is an order of birds formerly called Tubinares and still called tubenoses in English. ...

The conflicting molecular data is not much resolved by the fossil record. Modern loons are only known with certainty since the Eocene , but by that time almost all modern bird orders are known or strongly suspected to have existed anyway. The Late Eocene to Early Miocene genus Colymboides was widespread in Western and Central Europe; it is usually placed in the Gaviidae already, but may actually be more primitive; it is quite distinct from modern loons and could well be paraphyletic. From the genus Gavia, about a dozen fossil species have been discovered to date, which are known from the Early Miocene onwards and had a more southerly distribution (Brodkorb, 1953), like today's California, Florida and Italy. The following have been scientifically described: Three small ammonite fossils, each approximately 1. ... The Eocene epoch (55. ... The Miocene epoch is a period of time that extends from about 23 to 5. ... Official language(s) English Capital Sacramento Largest city Los Angeles Area  Ranked 3rd  - Total 158,302 sq mi (410,000 km²)  - Width 250 miles (400 km)  - Length 770 miles (1,240 km)  - % water 4. ... Official language(s) English Capital Tallahassee Largest city Jacksonville Largest metro area Miami Area  Ranked 22nd  - Total 65,795[1] sq mi (170,304[1] km²)  - Width 162 miles (260 km)  - Length 497 miles (800 km)  - % water 17. ...

• Gavia egeriana (Early Miocene of Czechoslovakia)
• Gavia brodkorbi (Late Miocene of Orange County, USA)
• Gavia concinna Wetmore, 1940 (Early - Middle Pliocene of W and SE USA) - may be same as G. portisi
• Gavia howardae Brodkorb, 1953 (Middle Pliocene of San Diego, USA)
• Gavia palaeodytes Wetmore, 1943 (Middle Pliocene of Pierce, USA)
• Gavia portisi Regalia, 1902 (Late Pliocene of Italy)
• Gavia fortis
• Gavia moldavica
• Gavia paradoxa
• Gavia schultzi

Undescribed fossils (Olson, 1985) are known from the eastern USA (Middle Miocene), Maryland (possibly Calvert Formation which is also Middle Miocene in age), and the Yorktown Formation (Early Pliocene at Lee Creek Mine, South Carolina where 3 unknown species are represented. Frank Alexander Wetmore (June 18, 1886 _ December 7, 1978) was an American ornithologist and avian paleontologist. ... Official language(s) None (English, de facto) Capital Annapolis Largest city Baltimore Area  Ranked 42nd  - Total 12,417 sq mi (32,160 km²)  - Width 90 miles (145 km)  - Length 249 miles (400 km)  - % water 21  - Latitude 37°53N to 39°43N  - Longitude 75°4W to 79°33... The Pliocene epoch (spelled Pleiocene in some older texts) is the period in the geologic timescale that extends from 5. ... Official language(s) English Capital Charleston(1670-1789) Columbia(1790-present) Largest city Columbia Largest metro area Greenville-Spartanburg-Anderson Area  Ranked 40th  - Total 34,726 sq mi (82,965 km²)  - Width 200 miles (320 km)  - Length 260 miles (420 km)  - % water 6  - Latitude 32°430N to 35...

In addition, there are some much older forms that are sometimes assigned to the Gaviiformes. From the Late Cretaceous, the genera Lonchodytes (Lance Creek Formation, Wyoming) and Neogaeornis (Quinriquina Formation, Chile) have been described; the latter is most probably a primitive loon, but may also be a hesperornithiform, and both have sometimes been allied with the orders which are considered related to loons. Doubtfully valid and surrounced by considerable dispute (Mayr, 2004) is the supposed Late Cretaceous loon Polarornis (Seymour Island, Antarctica). A piece of a carpometacarpus supposedly from Oligocene rocks near Lusk, Wyoming was described as Gaviella pusilla, but this also shows some similarities to the plotopterids (Olson, 1985). Geography of the US in the late Cretaceous Late Cretaceous (also called the Upper Cretaceous) refers to the second half of the Cretaceous period, named after the famous white chalk cliffs of southern England, which date from this time. ... The Lance Formation is a division of Late Cretaceous rocks in the western United States. ... Families Hesperornithidae Hesperornithiformes are an extinct and highly specialized order of Cretaceous toothed birds. ... Polarornis was a genius of a bird that appeared in the Late Cretaceous 76 mya. ... For North Seymour Island in the Galápagos Islands group, see: North Seymour Island. ... The Oligocene epoch is a geologic period of time that extends from about 34 million to 23 million years before the present. ... Lusk is a town located in Niobrara County, Wyoming. ... Genera Plotopterum Copepteryx Tonsala Phocavis The Plotopteridae were a family of flightless seabirds from the order Pelecaniformes. ...

Trivia

• The Common Loon is the national bird of Canada and is depicted on the Canadian one-dollar coin, which has come to be known affectionately as the loonie. It is also the official provincial bird of Ontario and the official state bird of Minnesota.

• The genus name Gavia is Latin for "Smew", even though loons are not related to smews.

• The European name "diver" comes from the bird's habit of catching fish by swimming calmly along the surface and then abruptly plunging into the water. The North American name loon comes from the bird's haunting, yodeling cry, a symbol of the Canadian wilds.

• Mercer, Wisconsin is identified as the "Loon Capital of the World."

• The Great Lakes Loons are a Single A baseball team based in Midland, MI.

See also loony (short for lunatic), which is sometimes spelled loonie. Loonie is the unofficial but commonly-used name for Canadas gold-coloured, bronze-plated, one-dollar coin. ... See also loony (short for lunatic), which is sometimes spelled loonie. Loonie is the unofficial but commonly-used name for Canadas gold-coloured, bronze-plated, one-dollar coin. ... Capital Saint Paul Largest city Minneapolis Area  Ranked 12th  - Total 87,014 sq mi (225,365 km²)  - Width 250 miles (400 km)  - Length 400 miles (645 km)  - % water 8. ... Latin was the language originally spoken in the region around Rome called Latium. ... Binomial name Mergellus albellus (Linnaeus, 1758) The Smew (Mergellus albellus) is a small duck which is intermediate between the mergansers and the goldeneyes, and has interbred with the Common Goldeneye. ... Mercer is a town in southren Iron County, Wisconsin, United States. ... League Midwest League Division Eastern Division Year founded 1995 Major League affiliation Los Angeles Dodgers Home ballpark Dow Diamond Previous home ballparks C.O. Brown Stadium City Midland, Michigan Current uniform colors red, black, green, silver Previous uniform colors green, black Logo design The wordmark Loons in red outlined in...

References

• Brodkorb, Pierce (1953): A Review of the Pliocene Loons. Condor 55: 211-214. PDF fulltext

• Mayr, Gerald (2004): A partial skeleton of a new fossil loon (Aves, Gaviiformes) from the early Oligocene of Germany with preserved stomach content. Journal of Ornithology 145: 281–286. DOI:10.1007/s10336-004-0050-9 (HTML abstract) PDf fulltext

• Olson, Storrs L. (1985): Section X.I. Gaviiformes. In: Farner, D.S.; King, J.R. & Parkes, Kenneth C. (eds.): Avian Biology 8: 212-214. Academic Press, New York.

The Condor is the quarterly journal of the Cooper Ornithological Society. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ...

External links

Wikimedia Commons has media related to:

Gaviidae

• Photo of a loon
• Loon sounds
• Loon videos on the Internet Bird Collection
• http://www.saskschools.ca/~gregory/animals/loon/ln2.html
• Loon Preservation Committee

Image File history File links Commons-logo. ... Wikimedia Commons logo by Reid Beels The Wikimedia Commons (also called Commons or Wikicommons) is a repository of free content images, sound and other multimedia files. ...